The present invention relates to an endless track mechanism for vehicles and self-propelling machines, for example for agricultural harvesting machines which are used under heavy ground conditions, for example on low load supporting grounds.
Endless mechanisms have the advantage over the substantially cost-favorable wheel mechanism, in that with good ground placement they cause low ground pressure and their use does not require planed or strengthened traveling floor. Endless track mechanisms are primarily used where high mass weights of heavy vehicles or machines must be transferred to low load supporting grounds, or a good and uniform ground adherence is required for example for overcoming a hilly or mountainous terrain. Vehicles and machines which can be used in these outside conditions are provided in accordance with their concept with a separate endless track mechanism adjusted to their constructions.
The known endless track mechanisms of the above mentioned general type usually have a torsion resistant central supporting frame fixedly connected with the frame of the machine or vehicle and supporting roller pairs articulated on its lower side and turnable in their holders. Supporting rollers which are supported in consoles are arranged on the upper side of the supporting frame. Such constructions are disclosed in U.S. Pat. No. 4,744,431 and in Soviet Union Patents 882,810 and 765,090. The front end of the supporting frame is provided with a deviating wheel for the endless track which is often identified as a deviating loop and in various known arrangements for an endless track mechanism is received by a device for adjusting and changing the endless track tension as disclosed in German documents DE 3 410 358 A1 and DE 2 539 019 C2. At the opposite side of the supporting frame, the drive wheel for the endless track is located which is identified as a drive loop which in some cases is connected with the machine or vehicle drive with interposition of a chain transmission or via hinge and Cardan shafts directly. Also, other solutions are known in which the rear end of each supporting frame and end transmission for the drive of each drive wheel is mounted and is driven separately for each drive wheel from a hydraulic motor or an electric motor or rotatably connected with the machine or vehicle drive by hinge or Cardan shaft. These solutions are disclosed in the German document DE 2 505 040 A1 and DE-AS 1 630 930.
German document DE-OS 2 161 154 discloses an endless track mechanism for a tractor which at the front side receiving working tool, wherein the running mechanism supporting arm is provided with longitudinal-thrust loadable thrust force-transmitting rod. This thrust force-transmitting rod which operates simultaneously as a supporting pipe forms a structural unit with the supporting frame and extends from the rear end of the mechanism frame, on which the drive wheel of the endless driving chain is supported to a front central tractor portion. Inside the thrust force-transmitting rod, a hinge shaft which transmits the drive torque to the drive wheel is provided. The endless track mechanism proposed in the German document DE-OS 2 161 154 is formed so that it directly takes up and transfers high thrust and pulling forces which occur in operation. Simultaneously, forces which are applied laterally to the working tool and located downwardly are absorbed better, whereby the total stability of the frame construction and the endless track vehicle is increased. The thrust force-transmitting rods which are articulately connected on the mechanism frame to a structural unit lead however to a cost unfavorable multiple loading and moreover requires additional space which often is not available.
In connection with this it must be further mentioned that the hollow supports with inwardly located chain or wheel drives are also known as well as hydraulic hoses guided in the hollow supports.